Intel 815 manual DWord Bit, Dest Buffer Format 0h = Any 8-bit Surface

Models: 815

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Intel® 815 Chipset: Graphics Controller PRM, Rev 1.0

R

DWord

Bit

Description

131:24 Reserved: 00h

23:20 Destination Origin Horizontal Bias: This is an unsigned value (0.4) that is used to bias the origin of the X values associated with the vertices of a primitive. The unbiased origin is located in the upper-left corner of a square pixel with the center located at 0.5,

0.5.A bias value of ½ (8h) would move the origin toward the right, such that an X value of 0.0 would specify the center of a pixel.

19:16

Destination Origin Vertical Bias: This is an unsigned value (0.4) which is used to

 

bias the origin of the Y values associated with the vertices of a primitive. The unbiased

 

origin is located in the upper-left corner of a square pixel/texel with the center located at

 

0.5, 0.5. A bias value of ½ (8h) would move the origin toward the bottom, such that a Y

 

value of 0.0 would specify the center of a pixel/texel.

 

 

15:14

Reserved: 00h

 

 

13:12

4:2:2 Channel Write Select: Select which channel(s) are written to the destination

 

buffer when the surface format is 4:2:2 using byte masks.

 

00

= Write all channels (Y,Cr, and Cb)

 

01

= Write only the Y channel

 

10

= Write only the Cr channel

 

11

= Write only the Cb channel

11Reserved (Additional Buffer Formats)

10:8 Dest Buffer Format: 0h = Any 8-bit Surface

1h = RGB 555 (16th bit is written as 0)

2h = RGB 565

3h = Reserved (ARGB 8888)

4h = 4:2:2 YCrCb (Y Swap format in memory)

5h = 4:2:2 YcrCb (Normal format in memory)

6h = 4:2:2 YcrCb (UV Swap format in memory)

7h = 4:2:2 YcrCb (UV/Y Swap format in memory)

7:2 Reserved: 00h

1 Vertical Line Stride: The number of lines to skip between logically adjacent lines. 0 = Do not skip any lines.

1 = Skip 1 line. (provides support for Interleaved/field surfaces)

0Vertical Line Stride Offset: The number of lines to add as an initial offset when the Vertical Line Stride is 1.

0 = Add no offset. (top field)

1 = Add 1. (bottom field)

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Page 252
Image 252
Intel 815 manual DWord Bit, Dest Buffer Format 0h = Any 8-bit Surface